Lobo the Marvel Dog, a German shepherd similar in appearance to Rin Tin Tin, receives top billing in this unusual and off-beat western melodrama, directed by Scottish-born Stuart Paton. The screenplay is credited to Jack Jevne, who authored or co-authored screenplays for "Topper," "Topper Takes a Trip," "Way Out West," and numerous Our Gang comedies, yet he stays clear of all comic relief in this melancholy work, telling an unhappy story in a bleak framework, some of his characters surviving only through stoic resignation to the terrible situations in which they are placed.
Bob McKenzie, in one of his best roles, is the honest sheriff and widowed father of Bobby Nelson, who also turns in one of his best performances. The incredibly evil Krouse (Barney Furey), trying to retrieve incriminating evidence from the sheriff's home, kills the youngster's beloved dog. While burying the dog, the boy is stunned to see another animal who looks exactly like his deceased pet - this dog owned, as it turns out, by a wandering prospector (Kane Richmond).
Jevne's tragic plot has enough twists and contrivances to keep it interesting. A teenage Fay McKenzie (Bob's daughter) plays a mistreated waif, and Eva McKenzie (Bob's wife) has a nice bit as a kind neighbor. Mr. Richmond hasn't much to work with and is given no opportunity for heroics, and stuntman/actor Frank Hagney does little with his assignment as a treacherous deputy.
Mr. Paton, veteran of silent films, allows no subtlety to detract from the struggle between unspeakable evil and laudable good. He hastens to tack on an artificially happy ending. At the time of its release, "Thunderbolt" received withering condemnation from Variety. Today, a lifetime or two later, devotees of 1930s B pictures, fans of the McKenzies and of Kane Richmond (and others in the cast), view this little melodrama from a vastly different perspective. Neither a typical western nor a typical dog story, "Thunderbolt" survives because cast and crew do their best to add life to a script filmed very swiftly and with no production niceties whatsoever, to serve as the bottom half of a double bill in the Depression years. Through that lens, its entertainment value is retained.
